VISITING SPEAKER: A universal code for RNA-protein recognition

RNA-protein complexes play essential roles in the regulation of gene expression, by orchestrating the basic growth and maintenance of the cell as well as the complex developmental programs of multicellular eukaryotes. The modes by which proteins bind RNA are diverse and often difficult to predict, limiting our ability to engineer RNA-binding proteins for practical applications. Engineering RNA-binding proteins is attractive because they could be fused to any desired effector domain, enabling selective binding of a specific RNA target to investigate or manipulate any aspect of its metabolism. We have used directed evolution to expand the recognition of Pumilio and FBF homology (PUF) repeats beyond adenine, guanine and uracil and evolved them to specifically bind cytosine. These repeat sequences can be used to create PUF domains capable of binding RNA targets of diverse sequence and structure enabling many potential biological and medical applications.